Silent launch gun for projectiles

ABSTRACT

A silent launching system for projectiles having a launch tube with a breech to receive a special cartridge and a constricted muzzle and containing a sabot. The projectile, such as an arrow, is loaded tail-first into the muzzle to contact the sabot. When the cartridge is fired, the sabot and projectile accelerate toward the muzzle, where the sabot is arrested in the constriction and the projectile continues out the muzzle to the target. The arrested sabot traps the expanding gases within the launch tube, providing a flashless, smokeless, and noiseless launch.

United States Patent [191 Swaim et al.

[ 51 Sept. 24, 1974 1 1 SILENT LAUNCH GUN FOR PROJECTILES [7 5]Inventors: Frank H. Swaim, Silver Spring; Raymond S. Widmayer, Laurel,both of Md.

[73] Assignee: The United States of America as represented by theSecretary of the Navy, Washington, DC.

[58] Field of Search 42/1; 89/1, 14 SB; 102/93 3,583,088 6/1971 Buck cta1 42/1 R 3,585,934 6/1971 Mueller et a] 42/1 L X 3,619,924 11/1971Paine 89/14 SB Primary Examiner-Samuel W. Engle Attorney, Agent, orFirmR. S. Sciascia; J. A. Cooke; Donn McGiehan [5 7 ABSTRACT A silentlaunching system for projectiles having a launch tube with a breech toreceive a special cartridge and a constricted muzzle and containing asabot. The projectile, such as an arrow, is loaded tailfirst into themuzzle to contact the sabot. When the cartridge is fired, the sabot andprojectile accelerate toward the muzzle, where the sabot is arrested inthe constriction and the projectile continues out the muz- [56]References Cited UNITED STATES PATENTS zle to the target. The arrestedsabot traps the expanding gases within the launch tube, providing aflashless, 32:23.5 89/8194lSg Smokeless and noiseless launch. 3I476Z04811/1969 Barr et a1. 89/14 SB X 3 Claims, 1 Drawing Figure \ll/l/ (li/1W" w) SILENT LAUNCH GUN FOR PROJECTILES BACKGROUND OF THE INVENTIONDESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings,there is shown in the This invention relates generally to launchers,guns, 5 FIGURE 11 Silent launch gun having an arrow 12 parpropellingsystems, ordnance and the like, and more particularly, to a flashless,smokeless, and noiseless propelling system for a projectile. The needfor such a silent launcher is apparent when one considers thedesirability of keeping the operators whereabouts unknown. Clandestinesneak attacks on enemies, and even the hunting of dangerous wild gameare but a few examples where the need to conceal the operators locationis important.

Alternatives to the use of an explosive charge to propel a projectileare obvious, and are the forerunners of the gun. The bow-and-arrow,probably the original propelling system, aside from lance throwing andslings, is powerful and accurate but is cumbersome to carry and use. Theblow gun and dart system is accurate, but lacks power for many purposes.The crossbow, has extreme propulsive power and accuracy, but is alsocumbersome to carry and to use.

The instant invention obviates the deficiencies of the ancient silentlaunch systems by providing a compact hand-held or rifle-attachablesilent launch system using explosive generated gas propulsion in aclosed chamber and barrel.

SUMMARY OF THE INVENTION Accordingly, an object of the present inventionis to provide a silent launch gun for projectiles.

Another object of the present invention is to provide a launch gun thatis smokeless, flashless, and noiseless.

A further object of the instant invention is to provide a launch gun theuse of which does not disclose the operators position.

A still further object ofthe instant invention is to provide a silentlaunch gun that is compact, readily carried through brush, and which maybe hand-held or adapted to be rifle mounted for firing.

Still another object of the instant invention is to provide a silentlaunch gun using an explosive propellant charge in a sealed chamber.

Briefly, these and other objects of the present invention are attainedby a short-barrel gun or launch tube having a breech to receive aspecial cartridge, a choked or constricted muzzle, and containing asabot. A projectile, such as an arrow, rests on the sabot when loadedtail-first into the muzzle. The projectile may be a plain arrow, orcarry explosives or incendiaries, or electronic surveillance equipmentsuch as listening and radio transmitting devices.

BRIEF DESCRIPTION OF THE DRAWING A more complete understanding of theinvention and the many attendant advantages thereto will be readilyappreciated as the same becomes better understood by reference to thefollowing detailed description, when considered in connection with theaccompanying drawing wherein:

The FIGURE is an isometric view, partially cut away, showing theprojectile launcher and a representative arrow projectile.

tially inserted in the muzzle.

The silent launch gun 10 is made up of several major components,comprising a tubular housing 14, having an externally threaded muzzle 16to receive a threaded end cap 18. End cap 18 has a center hole 20 toslidably accept a projectile 12. An O-ring seal 22 is contained in thecup-end of the end cap and is compressed against the muzzle end of abarrel 24 contained coaxially and pressed against a shoulder 26 withinthe tubular housing 14.

The breech end of the silent launch gun 10 contains a trigger and afiring pin assembly 28, a detailed discussion of which follows. A firingpin 30, is integrally formed as a cup-shaped plunger and slidablycontained within a reduced diameter bore 32 of the tubular housing 14and incidentally forms the shoulder 26. A striker 34 in the shape of ablunt-nose point is formed on the bottom outside of the cup-shapedplunger and coaxial with the plungers slidable motion. Vent holes 36surround the striker to preclude air pressure from slowing the firingpins 30 rate of travel. A spring 38, guided within the skirt of thefiring pin 30, biases it toward the breech end of barrel 24 whichcontains an explosive cartridge 40 having a percussion primer 70. Aspring seat pin 42 retains the spring at its other end and rests againsta trigger 44 formed as a crosspin in a transverse bore 46.

The trigger 44 has a plurality of annular grooves, two of which containO-ring seals 48. A pair oflarge diameter portions form the sear 50 ofthe trigger and thereby retain the firing pin 30 in the rearwardposition by residing in the round hole portions of a pair of key-holes52 in the skirt of the cup-shaped firing pin plunger. Rearward of theround holes and intersecting therewith, are subtending a pair of slots54 open at the edge of the skirt. These slots 54 are narrower than thediameter of the round hole portions, but are wider than annular grooves56 on trigger 44, thus permitting free movement of the firing pin 30when grooves 56 are aligned with slots 54.

The safety and arming mechanism comprises a bifurcated spacer 58 underthe head of the trigger 44 retaining it in the retracted position shown.A pull pin 60, and its associated pull ring (not shown) fastens thebifurcated spacer to the trigger 44 retaining it under the head until itis desired to arm the launch gun.

Referring now to the details of the construction of the barrel 24, ithas a constant diameter bore 64 except at the muzzle 16 where the barrelhas a choked constriction diameter 66. At the breech end of barrel isthe cartridge 40 threadingly engaged in the barrel 24. This cartridgecomprises a percussion primer and a black powder charge 72 sealed fromthe barrel by a flangible disk 74. Slidably contained within the barrelbore 64 is a sabot 76 having an O-ring seal 78 in an annular groove andin sliding sealing relationship with the bore 64. The sabot 76 has along-taper ogive portion 80 and a concentric counter-bore 82 in the noseportion, the function of which will be explained hereinafter.

In operation, the silent launch gun 10 may be handheld in the open, orthe breech end pressed against a stump or the like to absorb recoil, ormounted on a rifle by any convenient fastening means (not shown). Thesafety and arming mechanism is activated as desired to ready the launchgun for firing by manually pulling the pull ring and therefore the pullpin 60. The bifurcated spacer 58 is then slid from under the head of thetrigger 44, permitting it to be manually pushed inwardly. A projectilesuch as an arrow 12 is loaded tail first through the bore 20, the chokerestriction 66 of the muzzle, down the barrel bore 64 and into contactin counter-bore 82 of sabot 76.

The launch gun is then aimed at the target along a sightline determinedby experience, and fired by pressing the trigger 44. The inward movementof the trigger causes the large diameter sears 50 to slide a shortdistance through the round holes of the key-holes 52 aligning theadjacent annular grooves 56 on trigger 44 with the slots 54 of thekey-holes 52. The firing pin 30 is thence freed to slide forward in itscontaining bore 32 biased by spring 38. The striker 34 strikes thepercussion primer 70 of cartridge 40 and therefore initiates the blackpowder charge 72. The concomitant explosion and resulting gas expansionrapidly accelerates the sabot 76 and the contacting arrow projectile 12toward the intended target. Along the barrel, the gases are sealed in bythe O-ring 78 on the sabot. As the sabot 76 reaches the muzzle end 16,the long tapered ogive 80 engages the choke constriction 66 of thebarrel rapidly decelerating the sabot to a stop, and the subsequentmetal-to-metal interference fit positively seals the expanding gases inthe barrel 24, and the arrow 12 continues toward the target by its owninertia. Thus a smokeless, flashless, silent launch of a projectile isaccomplished which does not disclose the operators position.

Obviously, numerous modifications and variations of the presentinvention are possible in light of the above teachings. It is thereforeto be understood that, within the scope ofthe appended claims, theinvention may be practiced otherwise than as specifically describedherein.

We claim:

1. A silent launching system for projectiles comprising:

a tubular housing;

a barrel receivable in said housing having a breech end and a muzzleend;

an explosive cartridge threadedly disposed in said breech end;

a choke constriction in said muzzle end;

a projectile-driving sabot reciprocally constrained in said barrel,

said sabot having an end portion with a diameter greater than saidconstriction and a long-tapered, ogive nose portion,

whereby a controlled, rapid deceleration and a metalto-metal gas sealare provided by the collision of said sabot with said chokeconstriction;

a linearly reciprocating, transversely extending trigger having anenlarged head portion extending exteriorly of said tubular housing formanual operation;

a spring-biased firing pin coacting with said trigger and having acocked position and a released position; and

a safety device coacting with said enlarged head portion and having abifurcated spacer positioned between said head portion and said housingto preclude the release of said firing pin to the released position,

said bifurcated spacer being held in place by a removable pull pin andring.

2. The silent launching system of claim 1 wherein said barrel isremovable from said housing and a threadably removable,centrally-perforated muzzle end cap is provided for retaining saidbarrel in the launching system.

3. The silent launching system of claim 2 wherein said sabot has acounterbore in said nose for concentrically and releasably receiving andend of a projectile.

1. A silent launching system for projectiles comprising: a tubularhousing; a barrel receivable in said housing having a breech end and amuzzle end; an explosive cartridge threadedly disposed in said breechend; a choke constriction in said muzzle end; a projectile-driving sabotreciprocally constrained in said barrel, said sabot having an endportion with a diameter greater than said constriction and along-tapered, ogive nose portion, whereby a controlled, rapiddeceleration and a metal-to-metal gas seal are provided by the collisionof said sabot with said choke constriction; a linearly reciprocating,transversely extending trigger having an enlarged head portion extendingexteriorly of said tubular housing for manual operation; a spring-biasedfiring pin coacting with said trigger and having a cocked position and areleased position; and a safety device coacting with said enlarged headportion and having a bifurcated spacer positioned between said headportion and said housing to preclude the release of said firing pin tothe released position, said bifurcated spacer being held in place by aremovable pull pin and ring.
 2. The silent launching system of claim 1wherein said barrel is removable from said housing and a threadablyremovable, centrally-perforated muzzle end cap is provided for retainingsaid barrel in the launching system.
 3. The silent launching system ofclaim 2 wherein said sabot has a counterbore in said nose forconcentrically and releasably receiving and end of a projectile.